Method for the lixiviation of materials



Sept. 23 1924.

E. MORTERUD METHOD FOR THE mxxvnmou OF MATERIALS Filed Dec. 6. 1923 3 Sheets-Sheet l I IIIIIIEIIIIIIIIIIIIIM INVEN fosz Ezzvaz Maze TBBHD 4 TTOENEY Sept. 23 1924. H 1,509,686

a. MORTERUD METHOD FOR THE LIXIVIATION OF MATERIALS F1106 Dec. 6, 1923 3 Shoots-Sheet 2 INVENTQQ a T'TOQNEY E. MORTERUD METHOD FOR THE LIXIYIATION OF MATERIALS rum 0. e. 1923 3 Shoots-Sheet 3 [NYE N TDQ 522mg M012 2'52 w 617 Patented Sept. 23, 1924.

UNITED STATES PATENT OFFICE.- I

EINAR MORTERUD, OF TORDEROD, NEAR. MOSS, NORWAY.

METHOD FOR THE LIXIVIATION MATERIALS.

Application filed December 6, 1928. Serial No. 679,041.

To all whom it may concern:

Be it known that I, EINAR MoR'ranUn, a.

subject of the King of Norway, of Torderod,

' drawings, and to letters or figures of reference marked thereon, which form a part of this specification. v

In the lixiviation of materials a continuous process has been attempted by feeding the material to be lixiviated into the lower part of a vessel, comprising a screening device, while the lixiviation liquid is supplied at the top.

This method has proved to be unsuitable in,practice for the reason that it. has been impossible to achieve the absolutely necessary parallel'movement of evenly distributed material upwards in the vessel.

In order to satisfy this requirement it has been suggested to use a discontinuous process, the material being introduced during one interval of time, the lixiviation taking place in the next interval of time without sup-ply of material.

This object has been sought to be attained by making the screen which covers the whole area of the diifusor reciprocable in a vertical direction, while the feeding takes place in a space which is only filled by liquid and which is obtained by the screen having pressed the material upwards and thereupon returned to a position below the feeding opening.

The feeding accordingly takes place, laterally above the screen.

It is obvious that it is impossible to obtain an even distribution of material in this liquid filled space when the material is in troduced laterally. The material supplied obviously will be more or less diluted as it moves away from the feeding opening and the result is that the consistency of the material supplied will be uneven, what is exactly what it must not be.

In order to obtain the desired even distribution the only way is to introduce the material in a diluted condition upwards through the screening surface through particular channels or openings.

This may be obtained either by'making the screening surface stationary and using reciprocable' piston below this stationary screenlpg surface for effecting the raising movement, or the screening surface itself may form the piston. The screening piston may obviously be provided with holes or channels for letting the material through.

In order to prevent a successive filling up of the screening openings it is necessary at in tervals to remove the layer of solid material forming at'the top of the screening surface. If the material has the form of fibres, fibres Wlll obviously be pressed into the screening opening, and these fibres will adhere to the material on the top of the screening surface so as to form a layer with a more solid character than the material higher up in the vessel.

During the period of displacement the liquid supplied at the top of the vessel will replace the liquor to a certain depth, and the liquor will "be pressed out through the screen, the solid material being compressed upon the screen forming a continuous layer. The longer this period lasts, and the quicker the liquor is pressed through the screen, the more solid the layer of material will be.

The period ofdisplacement is followed by the period of supply, during which the layer on the screen is lifted somewhat by means of a return movement through the screening holes of a small quantity of liquor. Thereupon a new supply of material is introduced below said layer and upwards until the vessel is completely filled.

On the drawings Figs. 1, 1', 2, 3, 4 and 5 diagrammatically illustrate some forms of apparatuses for carrying out the invention.

With particular reference to Fig. 1 the vessel A is provided in its lower part by a screen S which is illustrated as comprising a number of narrow screening surfaces .9 with free passages between them. The liquor passing through the screen is collected in a tube a, which passes out through the wall of the vessel and is provided with valve arrangement I). The tube a is pro vided with a branch 0 which terminates in a device 01, illustrated as a cylinder with piston m which serves the purpose of pressing the small quantity of liquor out through the screening openings which is mentioned above and serves to clear the screening openin B is a movable bottom or piston, rovidz d with flap-valves e and reciprocate by means of rods f. a

In the bottom of the vessel opens a sup plying tube which is covered by flapvalve 12.. Tube g leads from the material storage tank C. At the top vessel A is provided with a channel, running round its periphe for taking up the lixiviated material which is removed from the surface of the vessel by means of scraping mechanism It, i. This scraping mechanism is illustrated as comprising two spiral arms 1', rotating about a central shaft is. Further the vessel is provided near its top with inlet openin 7 for introducing the displacing liquid.

he device here describedoperates in the following manner:

Vessel A is filled with material from C, valves 1)., e being opened by means of the pressure of materia Water is introduced through tubes Z, and valve 6 is opened, whereupon the first lixiviation period starts. Pistons B and m are in their bottom position. When the water supplied has dislaced so much liquor that the border surace which lies between water (displacing liquid) and original liquor lies between lines a: and y, the lixiviation period is finished and is followed by the supplying period. In the meantime tank C has been supplied with a quantity of material suflicient to cover the requirements of the next supplying period. The overflow edge n is adjusted to a level corresponding to this quantity.

The supplying period starts with the closing of valve 6 and an upward movement of piston m. Hereby a small quantity ofi liquor is pressed out through the holes of the screen, lifting the layer of material from the same. 7

Now piston B starts its u ward movement, as the piston valves 6 a back into closed position, while bottom val ve h opens. The quantit of material above B is now lifted para elly u wards, being pressed through passages tween the screening members and lifting the solid layer of fibres. When this movement ends, the dilusion zone a:y has been lifted to the position ar -g and a quantity of lixiviated material mixed with water has been removed into channel D by means of the scraping arms. Below piston B is placed the determined quantity of material from tank C. The valve in the bottom of C is closed, whereupon C is again filled with material, while a new period of lixiviation starts by the opening of valve 6.

During this period B and m return to bottom position, the material as regards B being pressed through the piston valves comingto rest at the top of piston B. The water (displacement liquid) through tubes Z may be running continuousl (although it is only required during the lixiviation period), and similarly the sore ing arms may work continuously. All t e movements which are necessary for the alternating lixiviation and supplying periods are taken off a common driving device in any known manner, for instance by means of cam discs, poles, links or'the like.

A modified arrangement is illustrated on Fig. 2. According to this form the screening surface is a continuous disc, covering a fiat chamber from the bottom of which the outlet tube (1. leads through the bottom of vessel A, being telescopically connected with a co-axial tube in order to enable the screen to be reciproca-ted so as to act as a piston.

The valves in piston B according to Fig. l are on Fig. 2 replaced by an annular o ning surrounding the screen and partly filled up by an annular member 1'. This annular mem er r is reciprocated in a vertical direction by means of rods 0, carrying the screening disc with it. vWhen movement takes place in an upwards direction, the annular body closes the opening, so that the contacts of the vessel above the screen are lifted. When the movement takes place in a downwards direction, the annular slot is opening, so that the material supplied be low the screen can be displaced to the upper side thereof.

Further Fig. 2 illustrates an arrangement by means of which the screening openings may be kept clear by causing a pulsation of the liquor below the screening surface.

The arrangement as illustrated comprises an annular diaphragm g, which is oscillated by means of rods p.

On Fig. 3 is illustrated an arrangement. in which screen and piston form an integral body. The screening surface is perforated by a number of channels m, which may all be closed by means of valves a, mounted on a screen which is again reciprocated by means of rods 0.

When the piston moves in a downward direction, valves e open for channels m until the screen carrying valves 6 abut against collar n on rod a. Then the screening surface is also pulled downwards to its bottom position. During the upward movement of rods 0 the screening plate is pressed upwards, valves (2 closing the channels n therein.

In order still further to secure an even mixture of liquid and material, the apparatus may be provided with a stirring upparatus, having arms t rotating in horizontal lanes.

is arrangement is illustrated on Fig.

l. The shaft 70 for the scraping arm i is extended downwards and provided with stirring arms t.

If stirring of the material below the surface is desired, the shaft as indicated in dotted lines may be extended below the screen and provided with arms on the underside thereof.

A rotating stirrin shaft u may also be introduced from the ottom of the vessel as illustrated on Fig. 5, the shaft passing freely through bottom valve 71..

On Fig. 5 it will be noted that the piston B is placed in a horizontal cylinder communicating through a tube G with the bottom of the vessel A. The tube gfrom the tank C (not shown of Fig. 5) communicates with the said horizontal c linder, and the piston'B is provided with ap valves in the same manner as in Fig. 1, although this is not shown on the drawing.

The object for placing piston B in the particular cylinder is to permit free work.- ing of the stirring arms t.

The screen tube a. is connected with ulsation cylinder 0!, as illustrated on. F1 1, although this pulsation cylinder is omitted on the drawing for the sake of clearness.

Claims 1. In a process of lixiviation of materials in a vessel provided with a screen covering its whole cross sectional area and where periods of feeding alternate with periods of lixiviation, the method which consists in introducing the material into the space above the screen from the underside of the screening surface through openings in the screening surface for the purpose of obtaining a mixture of the same consistency above the w ole of the screening surface, and of removing the solid deposits on the screening surface by means of the new material intro duced through the same.

2. An apparatus for use in lixiviation of materials, comprising a vessel, a screen therein, covering substantially the cross sectional area of said vessel, means for introducin the material to be lixiviated into the vesse below said screen and means for pressing the said material upwards through openings in the screening surface.

3. An apparatus for use in lixiviation of materials, comprising a vessel, a screen 1 therein, covering substantially the cross sectional area of said vessel, means for introducing the material to be lixiviated into the vessel below said screen and means for introducing diluted liquid '(water) above the said screen and a reciprocating iston for pressing the said material upwar s through openings in the screening surface.

4. -An apparatus form in lixiviation of materials, comprising a vessel, a screen therein, covering substantially the cross sectional area of said vessel, means for introducing the material to be lixiviated into the vessel below said screen, a reciprocating piston for pressing the said material upwards through openings in the screening materials, comprising a vessel, a screen therein, covering substantially the cross sectional area of said vessel, a reciprocating piston below the said screen, means for introducing the material to be lixiviated below the said reciprocating iston, said means comprising a. one-way va ve, and one-way valves in the said reciprocating piston for enabling the piston to press the said mate- ;ial through openings in the screening surace.

7. An apparatus for use in lixiviation of materials, comprising a. vessel, a screen therein, covering substantially the cross sectional area of said vessel, stirring means, comprising rotating arms in the vessel below the said screen, means comprising a cylinder and reciprocating piston for intermittently introducing material to be lixiviated. under pressure into the said vessel below the screening surface.

8. An apparatus for use in lixiviation of materials, comprising a vessel, 9. screen therein, coveringsubstantially the cross sectional area of said vessel, said surface com prisin a number of parallel screen ribbons or strips, forming the topof narrow channels whichcommunicate with an outlet tube for lixiviation liquid, means for producing back pressure in said outlet in order to cleanse the screening surfaces, means for introducin the material to be lixiviated into the vess below said screen and a reciprocating piston for pressing the said material upwards through openings in the screening surface.

In testimony that I claim the foregoing as my invention, I have signed my name in presence of a subscribin witness.

' 4 EINAB M RTERUD.

Witness:

MmonN'r Bust. 

